There have so far been well-known waterless light-sensitive lithographic plates including, for example, those comprising each a support coated thereon with a light-sensitive layer and an ink-repellent layer in order.
This type of waterless light-sensitive lithographic plates are developed after they are exposed imagewise to light. The developers applicable thereto include, for example, the organic solvent type developers such as those detailed in Japanese Patent Examined Publication No. 54-26923/1979, with which waterless light-sensitive lithographic plates are developed.
When using this type of the developer, the developments may be made at a satisfactory development rate on one hand, however, there raise the problems of inflammability, safety, or environmental pollution caused by the organic solvents on the other hand.
In the meantime, as for the developers prepared by taking the inflammability, safety and hygiene into consideration, the well-known aqueous type developers including those described in, for example, Japanese Patent Publication Open to Public Inspection -hereinafter referred to as Japanese Patent 0.P.I. Publication- Nos. 60-140243/1985 and 61-275759/1986. The techniques described therein are low in inflammability and excellent in safety because the developers contain water. However, these developers have the problem that the development efficiency is seriously deteriorated especially when processing a great number of plate materials with an automatic processor, because the development rate thereof is not high enough.
The present inventors have seriously studied on the above-mentioned problems and, resultingly, they have discovered that the problems can be solved by containing an organic carboxylic acid and at least one of a sulfite and a surfactant.